The present invention relates to valves and, in particular, it concerns a deluge valve with a valve seat drain.
It is known to provide a valve, often referred to as a “deluge valve”, for sealing and selectively opening a flow path from a water-filled inlet to a dry outlet for applications such as a sprinkler-based fire suppression system. The deluge valve is a normally-closed valve which prevents passage of water until the sprinkler system is to be activated.
In many systems, the deluge valve forms a barrier between an upstream water-filled pipe and a dry downstream pipe system leading to the sprinklers. Such implementations have particular advantages where the sprinkler system may be exposed to low temperatures such that water-filled pipes would be at risk of blockage from freezing. Where the downstream pipes are to be kept dry, it is considered unacceptable for the deluge valve to release even small quantities of water to the outlet pipes, and there is a consequent problem of reliability of such deluge valves when slight leaks occur, requiring inconvenient and expensive maintenance.